Monomethyl Ether Research Articles

Entropically and enthalpically driven self-assembly of a naphthalimide-based luminescent organic π-amphiphile in water.

The self-assembly of π conjugated systems in water has emerged as an efficient method for the development of functional materials for biological applications. But the process is more difficult to understand and to control in water compared to organic solvents due to hydrophobic effects. For π-conjugated molecules, self-assembly in solution generally occurs due to either an enthalpic or entropic gain, but designing π systems that undergo self-assembly via both an entropically and enthalpically favorable process is challenging. Herein, we elucidate in detail the self-assembly of a luminescent naphthalene monoamide-based dipolar π-bolaamphiphile appended with a primary amine and triethylene glycol monomethyl ether (NMI-W) side chain into a vesicular nanostructure. By utilizing a detailed isothermal titration calorimetry (ITC) experiment, we have calculated the thermodynamic parameters associated with the self-assembly of NMI-W in water. Interestingly, the NMI-W shows both entropically and enthalpically favorable robust self-assembly into a vesicular structure, which can encapsulate both hydrophilic and hydrophobic guest molecules. The synergistic effect of dipole-dipole, π-π stacking and hydrophobic interactions of the NMI chromophore is found to be very crucial in driving self-assembly in an aqueous medium as revealed by various experiments and molecular dynamics.

Decreasing Electrical Resistivity of Ag Film by Low-Temperature Evaporation and Sintering through Azeotrope Application

In the temperature-sensitive components, such as perovskite solar cells, large-area electrical connections with high electrical conductivity are also required. To fulfill the requirements, low-temperature evaporation was realized by preparing binder-free pastes with Ag flakes and a solvent mixture, followed by sintering at 140 °C. The mixed solvent was based on viscous α-terpineol with the addition of an appropriate amount of dipropylene glycol methyl ether acetate or diethylene glycol diethyl ether to achieve an azeotrope composition, followed by the addition of a low-molecular-weight hydroxypropyl cellulose to increase the viscosity and thixotropy. During sintering at 140 °C in air for up to 30 min, the paste with 49.5 wt% α-terpineol, 49.5 wt% dipropylene glycol monomethyl ether acetate, and 1 wt% hydroxypropyl cellulose mixture exhibited an excellent electrical conductivity of 7.72 × 10−6 Ω·cm despite the implementation of low-temperature sintering. The excellent processability of the prepared Ag-based pastes at 140 °C demonstrated their potential for novel application areas.

Longitudinal biomonitoring of mycotoxin exposure during pregnancy in the Yale pregnancy Outcome Prediction study

Mycotoxins are fungal toxins that may trigger adverse health effects in pregnant women and their unborn children. Yet, data is scarce on the dynamic exposure patterns of mycotoxins in pregnant women, especially in the United States. This study assessed mycotoxin exposure profiles (n = 50) from the Yale Pregnancy Outcome Prediction Study (YPOPS) cohort at four distinct time points. Multi-analyte human biomonitoring (HBM) assays based on liquid chromatography tandem mass spectrometry (LC-MS/MS), were developed for human serum and plasma matrices. The serum method was applied, together with an established urine method, to quantify mycotoxin levels in longitudinally collected matched serum (n = 200) and spot urine (n = 200) samples throughout pregnancy. The serum samples were mostly contaminated by the potential carcinogen ochratoxin A (detection rate: 49 %; median: 0.09 ng/mL), the hepato- and nephrotoxic citrinin (detection rate: 32 %; median: 0.02 ng/mL) and two enniatins (EnnB; detection rate: 97 %; median: 0.01 ng/mL and EnnB1; detection rate: 12 %; median: 0.003 ng/mL) which may act as immunotoxins. The most prevalent mycotoxins quantified in urine included deoxynivalenol (detection rate: 99 %; median: 23 ng/mL), alternariol monomethyl ether (detection rate: 69 %; median: 0.04 ng/mL), and zearalenone (detection rate: 63 %; median: 0.16 ng/mL). Seven other biomarkers of exposure including the highly estrogenic α-zearalenol and genotoxic Alternaria toxins, were also determined. Carcinogenic aflatoxins were not detected in any of the samples. Exposure assessment was based on the urinary data and performed by calculating the probable daily intakes (PDIs) and comparing the human biomonitoring guidance value (HBM-GV) for deoxynivalenol. The results showed that the individuals exceeded the tolerable daily intake (TDI) for deoxynivalenol and zearalenone on average at 28 % and 2 % over the different time points. Using the HBM-GV approach, the average exceedances for deoxynivalenol increased to 48 % indicating high exposure. For all the samples in which ochratoxin A was quantified, the estimated margin of exposure for neoplastic effects was below 10,000, indicating possible health concerns. Overall, this study showed that pregnant women were exposed to several regulated and emerging mycotoxins and that exposome-scale assessment should be a future priority in susceptible populations to better characterize xenobiotic exposure.

Influence of various cleaning solutions on the geometry, roughness, gloss, hardness, and flexural strength of 3D-printed zirconia

This study aimed to investigate the impact of various cleaning solutions on the geometry, roughness, gloss, hardness, and flexural strength of 3D-printed zirconia. Cleaning solutions, including isopropyl alcohol (IPA, 99.9%), ethyl alcohol (EtOH, 99.9%), and tripropylene glycol monomethyl ether (TPM, ≥ 97.5%), were diluted to a concentration of 70% and categorized into six groups: IPA99, EtOH99, TPM97, IPA70, EtOH70, and TPM70. Zirconia discs, printed via digital light processing, were sintered after cleaning. The geometry, roughness, gloss, hardness, and flexural strength were analyzed. Statistical analysis was performed using one-way ANOVA with Tukey’s post hoc test (p < 0.05). The thickness of TPM70 was the highest. The diameter of TPM70 was significantly larger than that of EtOH99 and IPA70 (p < 0.05). The weight of the TPM groups was significantly higher than that of IPA70 (p < 0.05). The roughness Ra of TPM70 was significantly greater than that of IPA99, EtOH99, and EtOH70 (p < 0.05). The differences in surface gloss, hardness, and flexural strength among the different groups were not statistically significant (p > 0.05). Different cleaning solutions did not affect the surface gloss, hardness, and flexural strength of 3D-printed zirconia. High and low concentrations of the same cleaning solution did not affect the surface gloss, hardness, and flexural strength. IPA70, TPM97, and EtOH can be considered viable post-printing cleaning alternatives to the traditional gold standard, IPA99.

A Stochastic FRET Study on the Core Dimension of Polystyrene-block-Poly(Polyethylene Glycol Monomethyl Ether Acrylate) Micelles.

Polystyrene-b-poly(polyethylene glycol monomethyl ether acrylate) (PSt-b-PPEGA) copolymers featuring pyrene and perylene as the Förster resonance energy transfer (FRET) donor (denoted as D-BCP) and acceptor (denoted as A-BCP), respectively, were synthesized via the reversible addition and fragmentation chain transfer (RAFT) polymerization. These copolymers were then used to form DA-mixed micelles via a dialysis method. The micelles consisted of D-BCP (mole fraction fD = 0.04), A-BCP (fA = 0.04), and label-free PSt-b-PPEGA (fN = 0.92). The decrease in fluorescence intensity of pyrene in the micelles confirmed the occurrence of FRET, with an observed efficiency of 0.32. A Monte Carlo approach was employed to estimate the expected FRET efficiency, assuming the random fractional distribution of D-BCP and A-BCP, along with the random spatial distribution of pyrene and perylene within the micellar core. The observed FRET efficiency suggested a core radius (Rc) of 0.95R0, where R0 was the Förster critical distance. With R0 calculated to be 3.2 nm based on Förster theory, Rc was determined to be approximately 3.0 nm, aligning closely with the dried-out core radius estimated from aggregation number and polystyrene density. This stochastic FRET methodology was further applied to investigate the swelling behavior of the polymer micelles in a mixture of N,N-dimethylformamide (DMF) and water. Dynamic light scattering analysis revealed minimal change in core dimension below 60 vol % DMF content. However, FRET analysis provided a deeper insight, showing an increase in core radius with DMF content up to 20 vol %, followed by saturation up to 50 vol %, offering a more comprehensive understanding of the micelle swelling behavior.

Determination of singlet oxygen quantum yield based on the behavior of solvent dimethyl sulfoxide oxidation by singlet oxygen

BackgroundPhotodynamic therapy (PDT) is emerging as a promising cancer treatment. The PDT efficacy is primarily attributed to the generation of singlet oxygen (1O2), stemming from the integrated effects of the photosensitizer, oxygen, and light. The singlet oxygen quantum yield (ΦΔ) serves as a bridge that links these parameters to the overall efficacy of PDT. The near-infrared luminescence of 1O2 provides a direct way for determining ΦΔ, but suffers from a poor signal-to-noise ratio. While the chemical trap probe method is detection-friendly, but it has a strict requirement for the excitation wavelength. Therefore, the existing methods for ΦΔ measurement are insufficient. ResultsIn this work, we developed an approach to determine ΦΔ of a broader range of photosensitizers using only the commonly used solvent dimethyl sulfoxide (DMSO), which can be oxidized by 1O2 to dimethyl sulfone. This method establishes the relationship between 1O2 production and changes in DMSO absorption spectra, eliminating the need for additional chemical probes. This method was validated by measuring the ΦΔ of rose bengal (RB) through systematic changes in absorption spectrum of DMSO under various RB concentrations and different excitation light power densities. Moreover, the ΦΔ of hematoporphyrin monomethyl ether (HMME), as determined by this method, is consistent with measurements obtained using the 1,3-diphenylisobenzofuran (DPBF) trapping probe. This consistency further validates the reliability of this method. Significance and noveltyThis work presents a direct, probe-free method to determine ΦΔ, reducing potential interference and expanding the range of useable excitation wavelengths. Its ability to measure ΦΔ using only DMSO enhances the accuracy of photosensitizer measurement, and broadens the applicability of the method to a wide range of samples, thereby advancing research on the properties of photosensitizers and further promoting the development of PDT.

Preparation of Glutathione-Responsive Paclitaxel Prodrug Based on Endogenous Molecule of L-Glutathione Oxidized for Cancer Therapy.

Using an endogenous carrier is the best method to address the biocompatibility of carriers in the drug delivery field. Herein, we prepared a glutathione-responsive paclitaxel prodrug micelle based on an endogenous molecule of L-glutathione oxidized (GSSG) for cancer therapy using one-pot synthesis. The carboxyl groups in L-glutathione oxidized were reacted with the hydroxyl group in paclitaxel (PTX) using the catalysts dicyclohexylcarbodiimide (DCC) and 4-dimethylaminopyridine (DMAP). Then, the amino-polyethylene glycol monomethyl ether (mPEG-NH2) was conjugated with GSSG to prepare PTX-GSSG-PEG. The structure of PTX-GSSG-PEG was characterized using infrared spectroscopy (FT-IR), nuclear magnetic resonance spectroscopy (NMR), and mass spectrometry (MS). The drug release kinetics of PTX within PTX-GSSG-PEG were quantified using ultraviolet spectroscopy (UV-Vis). The size of the PTX-GSSG-PEG micelles was 83 nm, as evaluated using dynamic light scattering (DLS), and their particle size remained stable in a pH 7.4 PBS for 7 days. Moreover, the micelles could responsively degrade and release PTX in a reduced glutathione environment. The drug loading of PTX in PTX-GSSG-PEG was 13%, as determined using NMR. Furthermore, the cumulative drug release rate of PTX from the micelles reached 72.1% in a reduced glutathione environment of 5 mg/mL at 120 h. Cell viability experiments demonstrated that the PTX-GSSG-PEG micelles could induce the apoptosis of MCF-7 cells. Additionally, cell uptake showed that the micelles could distribute to the cell nuclei within 7 h. To sum up, with this glutathione-responsive paclitaxel prodrug micelle based on the endogenous molecule GSSG, it may be possible to develop novel nanomedicines in the future.

Unraveling the fate of mycotoxins during the production of legume protein and other derived products

Consumers are increasingly looking for healthier and sustainable diets. Plant-based diets rich in legumes satisfy this demand. Legumes contain protein, dietary fibers and starch. Technological processes can separate these fractions, which can be used as supplements, or as ingredients. Nonetheless, legumes are susceptible to fungal infection, causing a potential health concern, since some fungi can produce mycotoxins: toxic secondary metabolites. The aim of this work was to analyze the fate of mycotoxins during different stages of the production process of legume derived products from the raw materials to final products. An extraction followed by liquid chromatography-tandem mass spectrometry was used for the analysis, revealing the presence of enniatin B (ENN B), alternariol monomethyl ether (AME), deoxynivalenol, T2-toxin, nivalenol, fumonisin B1 and sterigmatocystin in raw materials, intermediate products and side streams. The alkaline solubilization steps, were effective in reducing ENN B; however, AME was found in one of the final products.

Study of chili peppers and paprika contamination with alternaria toxins as health risk factors

At present, researchers show considerable interest in unregulated toxins of widespread fungi in nature, in particular, metabolites of microfungi of Alternaria genus. These toxins are potentially hazardous for human health and, under unfavorable conditions, capable of producing toxic metabolites, Alternaria toxins (AT), which have shown genotoxicity, mutagenicity and acute toxic effects. They are frequently detected not only in cereals and oilseeds, fruits, nuts, vegetables, but also in spices, especially dried red peppers. The aim of the study was to investigate the occurrence of Alternaria toxins in paprika and chili peppers sold on the domestic market as well as to assess their intakes by humans through their consumption. Concentration of 5 Alternaria toxins (alternatiol (AOH), alternariol monomethyl ether (AME), altenuene (ALT), tentoxin (TEN), tenuazonic acid (TeA)) was detected in 37 samples of dried red peppers marketed in Moscow and Moscow region in 2024 year including paprika (20 samples) and chili pepper (17 samples). The analysis of Alternaria toxins contamination was carried out by high-performance liquid chromatography coupled to tandem mass-spectrometric detection (HPLC-MS/MS). TeA was detected in 84 % of red pepper samples in concentration from 43 to 3295 µg/kg and TEN – in 40 % cases, in low levels ranging from 1.0 to 11 µg/kg. The occurrence of AT in paprika was higher than in chili pepper. Combined (2 or more toxins) contamination with Alternaria toxins was found only in paprika samples (65 %; the predominant combination is TeA and TEN). Intakes of Alternaria toxins associated with consumption of chili and paprika did not exceed the reference values and ranged from 0.0003 % (for TEN) to 0.24 % (for TeA) of the threshold of toxicological concern (TTC).

Результаты оценки контаминации перца чили и паприки альтернариатоксинами как факторы риска здоровью

At present, researchers show considerable interest in unregulated toxins of widespread fungi in nature, in particular, metabolites of microfungi of Alternaria genus. These toxins are potentially hazardous for human health and, under unfavorable conditions, capable of producing toxic metabolites, Alternaria toxins (AT), which have shown genotoxicity, mutagenicity and acute toxic effects. They are frequently detected not only in cereals and oilseeds, fruits, nuts, vegetables, but also in spices, especially dried red peppers. The aim of the study was to investigate the occurrence of Alternaria toxins in paprika and chili peppers sold on the domestic market as well as to assess their intakes by humans through their consumption. Concentration of 5 Alternaria toxins (alternatiol (AOH), alternariol monomethyl ether (AME), altenuene (ALT), tentoxin (TEN), tenuazonic acid (TeA)) was detected in 37 samples of dried red peppers marketed in Moscow and Moscow region in 2024 year including paprika (20 samples) and chili pepper (17 samples). The analysis of Alternaria toxins contamination was carried out by high-performance liquid chromatography coupled to tandem mass-spectrometric detection (HPLC-MS/MS). TeA was detected in 84 % of red pepper samples in concentration from 43 to 3295 µg/kg and TEN – in 40 % cases, in low levels ranging from 1.0 to 11 µg/kg. The occurrence of AT in paprika was higher than in chili pepper. Combined (2 or more toxins) contamination with Alternaria toxins was found only in paprika samples (65 %; the predominant combination is TeA and TEN). Intakes of Alternaria toxins associated with consumption of chili and paprika did not exceed the reference values and ranged from 0.0003 % (for TEN) to 0.24 % (for TeA) of the threshold of toxicological concern (TTC).

Synthesis and studies of manganese mercury thiocyanate glycol mono-methyl ether crystals for structural, electronic, dielectric, sensor and piezoelectric functionalities by theory and practice

Synthesis and studies of manganese mercury thiocyanate glycol mono-methyl ether crystals for structural, electronic, dielectric, sensor and piezoelectric functionalities by theory and practice

Unveiling dynamic alterations of lipid droplet polarity during NAFLD-triggered lipophagy utilizing a far-red fluorescent probe with large stokes shift

Lipophagy as a form of autophagy, can degrade lipid droplets, thereby acting as a critical regulator of cellular lipid metabolism, helping maintain the intracellular lipid homeostasis. In this study, we developed LP-SCUN, a far-red fluorescent probe for pinpointing lipid droplets with high sensitivity to solvent polarity. This probe allows for in situ imaging of lipophagy, tracking how lipid droplets move from non-polar to polar environments within lysosomes, leading to noticeable changes in fluorescence signals. The triphenylamine and triethylene glycol monomethyl ether groups of LP-SCUN facilitated its selective binding toward lipid droplets. Significantly, lipophagy and subsequent formation of autolysosomes decreased the environmental polarity, leading to a significant decrease in red fluorescence intensity (λex = 500 nm and λem = 643 nm). As such LP-SCUN was suitable for the in situ and real-time tracking of the cellular lipophagic processes. With this research we used LP-SCUN to elucidate the mechanism of lipid metabolism in liver cells of palmitate-induced hyperlipidemia cell models and high-fat diet-induced hyperlipidemia animal models. The results indicated that non-alcoholic fatty liver disease (NAFLD) can trigger an increase in cell lipophagy levels, while the inhibition of cell lipophagy can effectively alleviate the damage caused by NAFLD to cells and liver tissue in mice.

Preparation of chiral polyether dendrimer and its non-bonding immobilized CALB for high enantioselective synergy resolution of amines

Monodisperse polyethylene glycol monomethyl ether and chiral glycidyl tosylate were utilized as substrates in the synthesis of the chiral monomer unit epoxypropyl polyethylene glycol monomethyl ether (MPEGn-EPO). The initiator propargyl-terminated polyethylene glycol alkyne-PEG3-OH was employed, while the phosphazene base P4-t-Bu facilitated the controlled ROP of MPEGn-EPO, resulting in clickable dendritic P(MPEGn-EPO) with terminal alkyne. The chiral four-arm dendritic polymer 4-Arm-PEG3-Mn was synthesized through a click reaction between 4-Arm-PEG3-N3 and P(MPEGn-EPO) using Cu(PPh3)3Br/CuBr as a catalyst. Candida antarctica lipase B (CALB) was chosen as a model enzyme for the preparation of a non-covalently immobilized biocatalyst (CALB-M) via a simple adsorption process with magnesium silicate and 4-Arm-PEG3-M4-20. The immobilized lipase CALB-M16 demonstrated high enzyme activity in the resolution of racemic amines, yielding chiral amines with enantioselectivity up to 99 % ee. Circular dichroism (CD) analysis indicated the formation of helical conformation in the dendritic polyethers 4-Arm-PEG3-M16-20 in the presence of magnesium silicate at 5 °C. The polyethylene glycol side groups of 4-Arm-PEG3-M16-20 are suggested to potentially form a crown ether-like structure with magnesium ions, which could enhance steric hindrance and induce a right-handed helix. Furthermore, the helical structure of this dendritic polyether is thought to work in synergy with CALB, improving the enantioselective resolution of amines.

Investigation into the Potential of Paullinia pinnata (Linn.) Methanol Leaf Extract against Toxicity by Ethylene Glycol Monomethyl Ether in Wistar Rats

Investigation into the Potential of Paullinia pinnata (Linn.) Methanol Leaf Extract against Toxicity by Ethylene Glycol Monomethyl Ether in Wistar Rats

Synthesis and properties of a visual fluorescence-enhanced HClO/ClO- probe

Hypochlorite ion (ClO-/HClO) is a reactive oxygen species that plays a vital role in biological systems and daily life. The accurate detection of ClO- is critical for disease prevention and environmental monitoring. Therefore, it is necessary to develop highly sensitive probes. In this study, we report a visual fluorescence-enhanced HClO/ClO- probe CN-TPE-PEG1900, which was obtained by grafting poly (ethylene glycol) monomethyl ether 1900 with tetraphenylethylene (TPE) as the fluorescent parent. The fluorescence intensity of a solution containing CH3OH/H2O (30 μM, v/v, 1/4, PBS, pH = 7.4) and the probe CN-TPE-PEG1900 was increased by 9 times at 525 nm due to the presence of ClO-. The color of the probe CN-TPE-PEG1900 solution changed from yellow to colorless after reaction with ClO-. The limit of detection (LOD) of the probe CN-TPE-PEG1900 was 5.48 × 10–8 mol/L. In addition, it had a high fluorescence quantum yield of 51.27 %, a large Stokes shift of 165 nm, good water solubility, and high water sample recovery rates. The calculated data, 1H NMR, mass spectrometry, DLS, and SEM results were combined to deduce the recognition mechanism of the probe CN-TPE-PEG1900 for ClO-. Thus, the presence of ClO- facilitated the cleavage of the double bond in CN-TPE-PEG1900, thereby separating the water-soluble poly (ethylene glycol) chain from TPE through oxidative cleavage. Moreover, this led to the formation of TPE-CHO, which was less water-soluble and more prone to aggregation, resulting in fluorescence enhancement at 525 nm. Meanwhile, the process also caused a blue shift in the emission wavelength and a change in the color of the probe solution.

Deciphering and Integrating Functionalized Side Chains for High Ion‐Conductive Elastic Ternary Copolymer Solid‐State Electrolytes for Safe Lithium Metal Batteries

AbstractA critical challenge in solid polymer lithium batteries is developing a polymer matrix that can harmonize ionic transportation, electrochemical stability, and mechanical durability. We introduce a novel polymer matrix design by deciphering the structure‐function relationships of polymer side chains. Leveraging the molecular orbital‐polarity‐spatial freedom design strategy, a high ion‐conductive hyperelastic ternary copolymer electrolyte (CPE) is synthesized, incorporating three functionalized side chains of poly‐2,2,2‐Trifluoroethyl acrylate (PTFEA), poly(vinylene carbonate) (PVC), and polyethylene glycol monomethyl ether acrylate (PEGMEA). It is revealed that fluorine‐rich side chain (PTFEA) contributes to improved stability and interfacial compatibility; the highly polar side chain (PVC) facilitates the efficient dissociation and migration of ions; the flexible side chain (PEGMEA) with high spatial freedom promotes segmental motion and interchain ion exchanges. The resulting CPE demonstrates an ionic conductivity of 2.19×10−3 S cm−1 (30 °C), oxidation resistance voltage of 4.97 V, excellent elasticity (2700 %), and non‐flammability. The outer elastic CPE and the inner organic–inorganic hybrid SEI buffer intense volume fluctuation and enable uniform Li+ deposition. As a result, symmetric Li cells realize a high CCD of 2.55 mA cm−2 and the CPE‐based Li||NCM811 full cell exhibits a high‐capacity retention (~90 %, 0.5 C) after 200 cycles.

Deciphering and Integrating Functionalized Side Chains for High Ion-Conductive Elastic Ternary Copolymer Solid-State Electrolytes for Safe Lithium Metal Batteries.

A critical challenge in solid polymer lithium batteries is developing a polymer matrix that can harmonize ionic transportation, electrochemical stability, and mechanical durability. We introduce a novel polymer matrix design by deciphering the structure-function relationships of polymer side chains. Leveraging the molecular orbital-polarity-spatial freedom design strategy, a high ion-conductive hyperelastic ternary copolymer electrolyte (CPE) is synthesized, incorporating three functionalized side chains of poly-2,2,2-Trifluoroethyl acrylate (PTFEA), poly(vinylene carbonate) (PVC), and polyethylene glycol monomethyl ether acrylate (PEGMEA). It is revealed that fluorine-rich side chain (PTFEA) contributes to improved stability and interfacial compatibility; the highly polar side chain (PVC) facilitates the efficient dissociation and migration of ions; the flexible side chain (PEGMEA) with high spatial freedom promotes segmental motion and interchain ion exchanges. The resulting CPE demonstrates an ionic conductivity of 2.19×10-3 S cm-1 (30 °C), oxidation resistance voltage of 4.97 V, excellent elasticity (2700 %), and non-flammability. The outer elastic CPE and the inner organic-inorganic hybrid SEI buffer intense volume fluctuation and enable uniform Li+ deposition. As a result, symmetric Li cells realize a high CCD of 2.55 mA cm-2 and the CPE-based Li||NCM811 full cell exhibits a high-capacity retention (~90 %, 0.5 C) after 200 cycles.

Ultrasound-Activatable In Situ Vaccine for Enhanced Antigen Self- and Cross-Presentation to Overcome Cancer Immunotherapy Resistance.

Insufficient antigen self-presentation of tumor cells and ineffective antigen cross-presentation by dendritic cells (DCs) contribute to diminished immune recognition and activation, which cause resistance to immunotherapies. Herein, we present an ultrasound-activatable in situ vaccine by utilizing a hybrid nanovesicle composed of a thylakoid (TK)/platelet (PLT) membrane and a liposome encapsulating DNA methyltransferase inhibitor zebularine (Zeb) and sonosensitizer hematoporphyrin monomethyl ether (HMME). Upon local exposure to ultrasound, reactive oxygen species (ROS) are generated and induce the sequential release of the payloads. Zeb can efficiently inhibit tumor DNA hypermethylation, promoting major histocompatibility complex class I (MHC-I) molecules-mediated antigen self-presentation to improve immune recognition. Meanwhile, the catalase on the TK membrane can decompose the tumoral overexpressed H2O2 into O2, which boosts the generation of ROS and the destruction of tumor cells, resulting in the in situ antigen release and cross-presentation of tumor antigens by DCs. This in situ vaccine simultaneously promotes antigen self-presentation and cross-presentation, resulting in heightened antitumor immunity to overcome resistance.

Photopolymerization initiated by p-diethylene glycol monomethyl ether cinnamyl formamide-based disulfide under 455 nm LED with minimized volume shrinkage

This study introduces a novel p-diethylene glycol monomethyl ether cinnamyl formamide-based disulfide monomer, N,N′-(disulfanediylbis(2,1-phenylene)) bis(4-(4-(2-(2-methoxyethoxy)ethoxy) phenyl)-2-oxobut-3-enamide) (Mp-BSCF), designed to reduce the volume shrinkage of photosensitive resins and initiate monomer polymerization under 455 nm LED light irradiation. The photochemical properties and photoinitiation efficiency of Mp-BSCF are systematically investigated using UV–vis absorption spectroscopy, electron paramagnetic resonance (EPR) and real-time infrared spectroscopy. Although its weak absorption around 455 nm, Mp-BSCF can generate arylthiyl radicals under 455 nm LED irradiation, and then effectively initiate the polymerization of triethylene glycol dimethacrylate (TEGDMA)/A glycerolate dimethacrylate (Bis-GMA) system. Increasing Mp-BSCF addition enhances the final double bond conversion and maximum polymerization rate of the TEGDMA/Bis-GMA system, reaching up to 82.0 % and 2.02 % s−1, respectively. Notably, Mp-BSCF significantly reduces the volume shrinkage of the photopolymerization system, with the addition of 10 % Mp-BSCF resulting in a 50 % reduction compared to the control system. This reduction is attributed to the dynamic reversible nature of the SS bond “breaking-recovery” and the intermolecular hydrogen bond interaction. Additionally, Mp-BSCF improves the thermal stability, friction resistance, and hardness of the TEGDMA/Bis-GMA photopolymerization system.

Unraveling Interspecies Differences in the Phase I Hepatic Metabolism of Alternariol and Alternariol Monomethyl Ether: Closing Data Gaps for a Comprehensive Risk Assessment.

The Alternaria mycotoxins alternariol (AOH) and alternariol 9-O-monomethyl ether (AME) are pervasive food contaminants known to exert adverse effects in vitro, yet their toxicokinetics remain inadequately understood. Thus, this study endeavors to elucidate the qualitative and quantitative aspects of the phase I metabolism of AOH and AME. To pursue this goal, reduced nicotinamide adenine dinucleotide phosphate (NADPH)-fortified porcine, rat, and human liver microsomes were incubated for 0-10 min with AOH or AME within a concentration range of 1-100 and 1-50 μM, respectively. The decline in the parent toxin concentration was monitored via liquid chromatography coupled to tandem mass spectrometry, whereas coupling to high-resolution mass spectrometry provided insights into the composition of the arising metabolic mixture. The collected quantitative data allowed us to calculate the hepatic intrinsic clearance rates of AOH and AME, marking a notable contribution to the field. Moreover, we unveiled interspecies differences in the pattern and rate of the phase I metabolism of the investigated mycotoxins. The presented findings lay the groundwork for physiologically based toxicokinetic modeling aimed at estimating local concentrations of these mycotoxins in specific organs, enhancing our understanding of their mode of action and adverse health effects.